Cigarette filter



T. F. HUG

CIGARETTE FILTER Jan. 6, 1959 Filed Aug. 2, 1956 FIG] United StatesPatent r 2,867,219 CIGARETTE FILTER Thqma Hu S Ch l Application August2, 1956, Serial'No.-'601,fi62 .4-t3laim -(Cl- 111 2 -1 "This inventionrelates to cigarette filters, and more particularly to filters having animproved cooling 7 are concerned Wi-th inhaled -tar vapors. Although aconventional filter --is effective in trapping solid matter and liquiddroplets, there is room for improving other characteristics qfagfilter.Accordingly, one of the primarypbjects of the invention is to provide afilter having improved cooling and condensing action .Briefly, thisdisclosure contemplates a filter formed as a multipiece device includinga scalloped but otherwise impervious disc and an anterior mass offiltering material. Preferably, the filtering material includes afibrous front collector with its fibers running crosswise of thecigarette followed by a somewhat longer section of fibrous material withthe fibers running longitudinally.

The smoke is directed by the scallops at the edge of the disc so as topass adjacent the enclosing wrapper of the filter where the coolingeffect is at a maximum. It may also be noted that the notches in thescalloped disc serve to condense or compact the smoke, so that apartfrom the cooling effect, there is a greater tendency for the impuritiesto be intercepted and picked up by the filtering material behind thedisc. In other words, I have found that the fibrous filtering materialis more efiicient when the entering smoke is distributed through rathersmall openings as compared with a wide opening, as would be the case inthe absence of the scalloped disc. Ideally, the notches or scallopsshould be as small as possible, without clogging. As a result, aconsiderable amount of the tar is condensed out and is picked up by acollector immediately behind the disc. Moreover, the tobacco tars tendto accumulate in the center portion of the filter so as not to interferewith the draw.

Other features of the invention will be in part apparent from and inpart pointed out in the following detailed description taken inconnection with the accompanying drawings, in which:

Fig. 1 is a longitudinal section illustrating a cigarette and filterembodying the invention;

Fig. 2 is a cross section taken on the line 22 of Fig. 1;

Fig. 3 is a cross section taken on the line 3-3 of Fig. 1; and

Fig. 4 is a cross section taken on the line 44 of Fig. 1.

Before considering the detailed structure of the filter, it may behelpful to look at the cigarette itself. The smoke fro-m the burningtobacco is initially hot and contains solid matter, moisture and tarvapors. As the smoke is drawn rcarwardly through the unburned tobacco,some filtering occurs and the smoke has an opportunity to cool.

On the other hand, this inherent filtering and cooling actionnecessarily depends upon the length of the unfibrous materialofthe-filter is fine and closely spaced,

thereby being a more effective trap, but the distribution of the smokein the filter may not be uniformya factor 'that .becomes aggravated astars accumulate.

.T'he problem of uniform distribution has involved the introduction oflongitudinal guide tubes, such as-rolled corrugated paper and thecooling problem has been handled by lengthening the path of the smoke.'The present invention is directed to a different arrangement wherebycoolingaction and smoke -distribution are controlled simultaneously.

vReferring nowto the drawings,rthere is shown a cigarette comprising theusual paper wrapper 1 and filling oflobacco 3. The filter comprises anouter tube-like mouthpiece or tip 5 secured to the back of the wrapperofcigarette'paper :1. The anterior portion of tip 5 is filled .withamass of filtering material 7, and as such, .the f filter is similar toconventional types.

The'jinvention more specifically lies in .theprovision of a disc :9 ofrelatively impervious material disposed imm'ediately'behind-the tobacco3 at the forward end of the filter. This disc may be formed of paperwith a diameter corresponding to the inside dimensions of themouthpiece, but it is scalloped so as to provide a plurality of notches11 spaced about its margin. The scalloped disc thereby causes all of thesmoke to be guided outwardly against the tip or wrapper 5 beforeentering the main portion of the filter.

There are several reasons for this arrangement. In being directedoutwardly, the smoke necessarily comes in contact with the wrapper, sothat the cooling action is at a maximum. As the smoke is cooled in itspassage around the disc, a substantial portion of the tar tends tocondense out in the center portion of the filter, and the smoke isbroken into several discrete paths for improved distribution preparatoryto its passage through the main portion of the filter.

Apart from the cooling effect, there is a second and perhaps moreimportant action resulting from the scalloped disc. The disc necessarilyreduces the cross section of the draft (as compared with a conditionwithout a disc) so that the smoke is condensed or compacted as it entersthe fibrous filtering material. When the smoke is confined in thismanner, the fibrous material seems to have a better filtering action anda larger proportion of the impurities are picked up in the filter (ascompared with a conventional filter which opens direct to the tobaccoacross the entire cross section of the cigarette).

The filter otherwise comprises a fibrous collector 13 locatedimmediately behind the disc 9 and the fibrous section 7 filling the restof the tip. The collector is a rather short piece and may be cut from asheet of matted fibers. As such, the fibers of the collector extendcrosswise to the axis of the cigarette, whereas the longer fiber section7 preferably has its fibers extending lon itudinally. In operation, asubstantial portion of the condensed tar vapors accumulate in thecollector well ahead of the center portion so as not to interfere withthe draft or draw of a cigarette. The result is that there is lessinhaled tar, more uniform draw throughout the smoke and reducedtemperature with improved mildness and better flavor.

From the foregoing description, it is apparent that those skilled in theart will understand the structure, function and mode of operation of theinvention herein disclosed, and appreciate the advantages thereof. Al-

though one embodiment it is to be understood that the invention is notlimited has been disclosed in detail,

thereto, but the drawings and description thereof are :to be undersoodas being merely illustrative. It-is realized that many modifications andvariations will present themselves to those skilled in the art Withoutdeparting from the spirit of this invention or the scope'thereof as setforth in the appended claims. 7

}Having thus described the invention, What is claimed and desired tobesecured by Letters Patent is:

1. In a cigarette filter having a tube-like mouthpieceextendingrearwardly from a cigarette, the improvement comprising a discof relatively impervious material 10- I cated adjacent the front of themouthpiece, said disc being formed with openings of uniform sizeuniformly disposed solely about its periphery so as to direct andconcentrate flow of smoke adjacent the wall of the .mouthpiece, and amass of fibrous filtering material lector of fibrous material locatedimmediately behind said disc to intercept the smoke upon leaving theopen- .4 ings of said disc, said collector having its fibers extendingcrosswise with respect to the axis of the cigarette.

3. A cigarette filter as set forth in claim 2, further including asection of fibrous material located in the mouthpiece behind saidcollector, said last section being of relatively greater length than thecollector and having its fibers extending longitudinally with respect tothe filter.

4. In a cigarette filter having a tube-like mouthpiece extendingrearwardly from a cigarette, the improvement comprising a disc'ofrelatively impervious material located adjacent the front ofthemouthpiece, said disc being formed with a scalloped periphery todefine a plurality of uniformly shaped openings spaced uniformly aboutits periphery so as to direct and concentrate flow of smoke adjacent thewall of the mouthpiece, and a mass of filtering material disposed behindsaid disc to intercept the smoke upon leaving the openings of said disc.

References Cited in the file of this patent UNITED STATES PATENTS984,742 Blosser Feb. 21, 1911 1,310,404 Irving July 15, 1919 252,707,960 'Janecke May 10, 1955 FOREIGN PATENTS r 59,941 Germany Dec.15, 1891 1,101,759 France Apr. 27, 1955

